Future wireless telephone systems will use coordinated transmissions across multiple cells within each cell-site or across multiple cell site. This is called Coordinated Multipoint Reception (CoMP). CoMP operation enhances coverage to UEs hitherto experiencing poor coverage because they are served using just a single cell. UEs benefiting from CoMP are labeled advanced UEs.
CoMP operation requires accurate channel state information (CSI) knowledge at the advanced user equipment (UE). CSI refers to the multi-dimensional channel matrix between each coordinating cell (the CoMP cell) and the advanced UE.
Assume that the advanced UE has a single primary serving cell and N secondary cells which coordinate their transmissions. The coordinating cell set serving the advanced UE of interest are labeled {CoMP Cell0, CoMP Cell1, . . . , CoMP CellN}. In a prior standard there were no coordinating cells so N=0.